Electrical translating apparatus



Dec. 13, 192.2. P, H, DOWUNG 1,891,044

Filedl March 25, 1930 Patented Dec. 13, 1932 PHILIP H. DOWLING, OFSWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY,0F SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA ELECTRICALTRANSLATING APPARATUS Application led March 25. 1930. Serial No.438.916.

My invention relates to electrical translating apparatus, andparticularly to apparatus of the type comprising an input circuit whichis at times supplied with current and an output circuit in which theflow of current is controlled 'in accordance with the current suppliedto the input circuit.

One feature of my present invention is the provision of electricaltranslating apparatus of the type described, in which substantially nocurrent is delivered by the output circuit when the current supplied tothe input circuit is of normal Value.

I will describe two forms of electrical translating apparatus embodyingmy invention, and will then point out the novel features thereof inclaims.

In the accompanying drawing, Fig. 1 is a diagrammatic View illustratingone form of electrical translating apparatus embodying my invention asapplied to the control of. a trackway signal. Fig. 2 is an end View ofthe translating apparatus shown in Fig. 1. Fig. 3 is a diagrammatic viewshowing a modified form of the apparatus shown in Figs. 1 and 2 and alsoembodying my invention. Fig. 4 is an end View of the core A of Fie. 3.

imilar reference characters refer to similar parts in each of theseveral views.

Referring to Figs. 1 and 2, the reference character T designates atransformer which, as here shown, comprises two cores A and B ofmagnetizable material. Core A is of the well known shelll type, andcomprises three legs l, 2 and 3 connected in parallel to form twomagnetic paths with the leg 2 forming a bridging member common tobothpaths. The core B is shown as a single path core, but this particularform is not essential. Alternating flux is supplied to the transformer Tby a primary winding 4 which links the end leg 3 of core A and whichalso links the core B. The winding 4 is supplied with periodic currentfrom some suitable source here shown as an alternating current generatorG. The reference character 6 designates a secondary or output windingwhich supplies energy to any suitable output circuit. Winding 6 alsolinks core B and the leg 3 of core A.

For the purpose of controlling the electromotive force induced inwinding 6, an input Winding 8 is located on the bridging member -ormiddle leg 2. of core A and current is at times supplied to this windingto vary the permeability of core A. It is preferable, though notessential, to supply the winding 8 with unidirectional current, and ifthe source of controlling current 'delivers alternating current, arectifier K may be included in circuit with winding 8. The parts are soadjusted that when a predetermined value of current is supplied towinding 8 (usually when this current is Zero), substantially no currentis drawn by the device supplied from the output circuit. As shown in thedrawing, this adjustment is accomplished by loeating cores A and B inplanes disposed at an angle. As here shown, this angle is substantially90, and the windings 4 and 6 are also disposed at an angle so that theiuxes created in the cores A and B by current in the primary Winding 4ow in opposite directions at the same instant through the output winding6. The proportions of the parts are such that the net electromotiveforce induced in winding 6 for Zero current in winding 8 issubstantially zero. This result can be accomplished by proportioning theparts so that under` normal conditions the iux from winding 4 dividesequally between cores A and B. If the iuX density in core A were equalto the flux density in core B, the electromotive force induced inwinding 6 would remain at zero for all voltages applied to winding 4.Since it is inconvenient to construct the parts with equal densities forthe two cores, it is desirable to work the iron of each core at a pointsufficiently high onits saturation curve that the changes in thepermeabilities of the two cores will be substantially equal over a Widerange of variation of the voltage applied to the winding 4. With thisadjustment, the zero value of induced electromotive force in winding 6will be substantially independent of Variations in the electromotiveforce' supplied by generator G.

lVhen current is supplied to winding 8 there is created in the middleleg 2 of core A, a magnetic flux which decreases the permeability ofcore A to flux resulting from current flowing through winding 4. Theresult is that the primary flux from winding 4 in core A is decreasedand a correspondingly greater proportion of this primary flux. is forcedthrough core B. These changes 1n the distribution of flux from winding 4are cumulative in their effect on winding 6 and the result is that anelectromotive force is induced in the winding 6 which is available tosupply current to the device connected therewith. Furthermore, it willbe apparent that a c0111- paratively small change in the currentsupplied to Winding 8 will producev a comparatively large change in thecurrent supplied to device 7 by winding 6.

In order to prevent the passage of alternating flux throu h the middleleg 2 of core A, I prefer to p ace a conducting sleeve 5 around thisleg, thereby forcing the alternating flux'Y through legs 3 and l andpreventing feed-back into the control winding 8 and the circuitsconnected therewith.

Although the apparatus may be utilized to control the supply of currentto 4any form of output load, I have shown it controlling a signal lamp 7in a railway signaling system. Thus E-F is a section of railway trackwhich is normally supplied with current from a track transformer Hconnected across the rails adjacent one end of the section. The inputwinding 8 of transformer T is connected, through the rectifier K, acrossthe rails adjacent the other end of the section. The lamp 7 controlledby output Winding 6 may then indicate proceed trafic conditions insection E-F. It will be plain that when section E-F is unoccupied,current is supplied to the winding 8 and lamp 7 is then lighted. Ifsection E-F is occupied by a train, however, current is shunted awayfrom winding 8 and the fluxes in cores A and B will then be equal sothat no electromotival force is induced in winding 6 and lamp 7 is thenextinguished.

In addition to the parts thus far described it may be desirable, in someinstances, to make the transformer T, regenerative. This may beaccomplished by placing a winding 9'on the middle leg 2 of core A andsupplying energy to this winding from the secondar winding 6 through arectifier K1. With this construction, it will be plain that when currentis not being supplied to the input winding 8 so that no electromotiveforce is induced in winding 6, no current is supplied to winding 9. Whenthe input winding is energized, however, thus destroying the normalbalance between the fluxes in the cores A and B, the resultingelectromotive force in winding 6 is available to supply current towinding 9. The parts are so connected that the current thus supplied towinding 9 creates in leg 2 of core A, a flux which aids the flux createdby current in winding 8, and therefore assists in decreasing thepermeability of core A. This change causes a further increase in theelectromotive force induced in winding 6 and the cycle of operationcontinues until a state of equilibrium is reached.

It is apparent that by means of the winding 9 a ratio of amplificationcan be obtained which is greater than that conveniently obtained Withoutthe use of this winding.

Rectifier K1 may be connected across a sufficient portion ot' thewinding 6 to obtain the desired results, and it should be noted in thisconnection that if the degree of regeneration is sufficient it ispossible to adjust the parts so that once the electromotive forceinduced in winding 6 has become sulliciently high due to the presence ofdirect current in winding 8, the output will not return to zero when thesupply of current to winding 8 is discontinued. The operation of thetranslating device, under these conditions, is analogous to theoperation of a stick relay and after the supply of current to the load 7controlled by winding 6 has once commenced it can not be interrupted bydiscontinuing the supply of current to the input winding 8.

In the modified form of .apparatus illustrated in Figs. 3 and 4 thevsame principles are utilized as in the modification described above,but the arrangement of parts is somewhat dii'erent. The core B is aclosed magnetic core .similar to that shown in Figs. 1 and 2, but coreA, as shown in Figs. 3 and 4 is shaped somewhat like a figure 8. The endlegs 1 and 3 of core A are adjacent to and parallel with opposite sidesof core B, and the middle leg 2, as here shown, is at right angles withthese legs and carries the conducting sleeve 5 and the input winding 9.The primary winding 4 is connected with the alternator G and links theend leg l of core A and the adjacent portion of core B. Secondarywinding 6 is connected with the load 7 and links the leg 8 of core A andthe adjacent portion of core B. The parts are so proportioned that whenno current is being supplied to the input Winding 9, the primary fluxdelivered by primary winding 4 divides equally between cores A and Bi Itwill be seen that the luxes in cores A and B traverse the secondarywinding 6 in opposite directions, so that' for zero input to winding 9,no current is supplied to the load 7. When current is supplied toWinding 9, however, the permeability of core A is decreased, so that anincreased proportion of the primary flux from winding 4 traverses coreB. As a result, there is induced in secondary 6 an electromotive forcewhich supplies current to the load 7.

It will be seen from the foregoing that the same principles are involvedin both embodiments of my invention herein shown and described, and thatin both cases the secondary winding is linked by two magnetic paths inwhich the fluxes are balanced for normal values of input current, butare unbalanced 5 to produce a resultant induced secondaryelectromotiveforce when the input current has any other value.

Although I have herein shown and describedy only two forms of electricaltranslating apparatus embodying my invention, it is understood thatvarious changes and modifications may be made therein within the scopeof the appended claims without dearting from the spirit and scope of myinvention.

Having thus described my invention, what I claim is:

1. A transformer comprising a first winding supplied with periodiccurrent, two magnetic paths both linking all of said first winding, asecond winding linking both said magnetic paths in such manner that thefiuxes 1n said paths due to current in said first winding induceopposing electromotive forces in such second winding, and means forcontrolling the distribution of iux from said first winding between saidtwo paths.

. 2. A transformer comprising a first winding supplied with periodiccurrent, two magnetic paths both linking all of said first winding, asecond winding linking both said magnetic paths in such manner that thefluxes in said paths due to current in said first winding induceopposing electromotive forces in 5 such second winding, a third windingassociated with one said path, and means for at times supplying currentto said third winding to vary the distribution of flux from said firstwinding between said two paths.

3. A transformer comprising a first winding supplied with periodiccurrent, two magnetic paths both linking all of said first winding. asecond winding linking both said magnetic paths in such manner that theresultant electromotive force normally induced in such second winding issubstantially zero, and means for at times varying the permeability ofone said magnetic path to vary the distri'buton of flux from said firstwinding between said two paths. y

4. In combination, two magnetizable cores having adjacent portionsdisposed in angular relation, two windings each embracing the adjacentportions of both said cores and disposed in angular relation, means forsupplying periodic current to one said winding, and means for varyingthe permeability of one said core to vary the electromotive forceinduced in the other said winding.

5. In combination, two magnetizable cores having their planes disposedin intersecting planes, two windings disposed in intersecting planes andboth linking the same portions of both said cores, means for supplyingperiodic current to one said winding, and means for at times varying thepermeability of one said core to vary the electromotive force induced inthe other said winding.

6. In'combination, a closed magnetic core, a shell type core disposedyat an angle with sald closed core and having one end leg adjacent a legof such closed core, two windings disposed at an angle and both linkingthe adjacent legs of both said cores, means for supplying periodiccurrent to one said winding, a third winding on the middle leg of saidshell type core, and means for at times supplying current to said thirdwinding to vary the permeability of the associated core.

7. In combination, a first winding supplied with periodic current, twomagnetizable cores each threading all of said first winding and normallycarrying equal portions of the iux created by current in such firstwinding, a

second winding linking both said cores in such manner that the resultantelectromotive force induced therein by equal fluxes in said cores issubstantially zero, and means for at times decreasingthe flux in onecore and simultaneously increasing the fiux in the other core to producea material electromotive force in said second winding.

8. In combination, a first winding supplied with periodic current, twomagnetizable cores both linking said first winding` a second windinglinking both said cores, means for varying the permeability of one saidcore to vary the electromotive force induced in said second winding, andmeans responsive to the electromotive force induced in said secondwinding for varying the permeability of said one core. v

9. In combination, a. closed magnetizable core, a shell type coredisposed at an angle with said closed core and having one end legadjacent a leg of such closed core, two windings disposed at an angleand both linking the adjacent legs of both said cores, means forsupplying periodic current to one said winding, a conducting sleevelocated on the middle ieg of said shell type core, a third winding onthe middle leg of said shell-type core, and means for at times supplyingcurrent to said third winding to vary the permeability of the associatedcore.

l0. In combination, two windings, means for supplying periodic currentto one said winding, two magnetizable cores each linking both saidwindings in such manner that the fluxes produced in said cores bycurrent in said one winding flow in opposite directions at an instantthrough the other winding, means for varying the permeability of onesaid core to vary the electromotive force induced in said secondwinding, and means responsive to the electromotive force induced in saidsecond winding for varying the permeability of said one core.

l1. In combination, two windings, means for supplying periodic currentto one said winding, two magnetizableores each linking both saidwindings in such manner that the fluxes produced in said cores bycurrent in said one winding 'low in opposite directions at an instantthrough the other winding, means for varying t-he permeability of onesaid core to vary the electromotive force induced in said secondwinding,'and a third winding on said one core receiving ener from saidsecond winding -for varying t e permeability of said one core.

12. In combinatiomtwo windings, means for supplying periodic current toone said winding, two magnetzable cores each linking both said windingsin such manner that the fluxes produced in said cores by current in saidone winding fiow in opposite directions at an instant through the otherwinding, a thrd winding on one said core, means for at times supplyingcurrent to said third Winding to vary the electromotive force induced insaid second winding, a fourth winding on said one core, and meansresponsive to the electromotive force induced in said second winding tosupply current to said fourth winding to increase such variations in theelectromotive force induced in said second winding.

13. In combination, two windings, means for supplying periodic currentto one said winding, two magnetizable cores each linking both saidwindings in such manner that the fluxes produced in said cores bycurrent in said one winding flow in opposite directions at an instantthrough the other winding, means for at times varying the permeabilityof one said core to change the electromotive force induced in saidsecond winding, a third winding on one said core, and means responsiveto the electromotive force induced in said second winding for supplyingenergy from said second winding to saidthird winding to increase suchchanges in the electromotive force induced in said second winding.

14. In combination, two windings, means for supplying periodic currentto one said winding, two magnetizable cores each linking both saidwindings in such manner that the fluxes produced in said cores bycurrent in said one winding` iow in opposite directions at an instantthrough the other winding, means for at times varying the permeabilityof one said core to change the electromotive force induced in saidsecond winding, a third winding on one said core, and means including arectifier for supplying energy .from said second winding to said thirdwinding..

In testimony whereof I aiiix my signature.

PHILIP H. BOWLING.

